1. Field of the Invention
There are a plethora of products which are packaged in dry particulate form, even though a more efficient state for use may be liquid. The risk of spills requiring cleanup and disposal is reduced, and any spill of dry is cleaned up easily. Dry matter is simply more easily stored and handled, and in dry form, the user is not required to handle the weight of, or pay for, the addition of liquids, such as water.
Many dry products are not readily liquid or water soluble, and in such products, maintenance of a proper concentration during dispensing of the resultant slurry creates additional problems.
In the area of soil amendments, and particularly such amendments as gypsum, potassium, sulfate, ammonium sulfate and some fertilizers, systemic herbicides, and pesticides, the problems are sufficiently complex that manual mixing and application has become the norm, even though many of such products are more efficiently applied by injection into an irrigation system.
As in other methods of application, irrigation systems differ in both their theory and application. Perhaps the most familiar system in current use is the sprinkler systems, which are similar to residential lawn sprinklers, and rely on timing to lay down a specific volume of water, commonly expressed in terms of acre feet/acre or acre inches/acre as applied.
Also in use, because of its simplicity for a particular application, is flood, or furrow application, wherein a particular parcel is leveled so as to provide a decrease in elevation away from the source of irrigation water. Small dikes are provided to retain the water until it can be absorbed, Thus, when the water is turned on the water flows away from the source and floods the parcel.
In certain row crops, furrow irrigation is employed. Similar to flood irrigation, a peripheral canal is flooded with water, and syphon tubes are used to interconnect successive rows of furrows with the canal to flood them.
Particularly in the more arid planes of the western states, where water is often at a premium, many agriculturalists have, as a means of water conservation, installed drip irrigation equipment, which delivers a proper amount of water directly to the base of the plant. Such a system does not work in all cases, but is effective in tree and vine cultivation.
If, as is the underlying philosophy of the present invention, soil amendments are best applied by injection into the irrigation system, in order that they might be carried into the soil with irrigation water, then the vexing problem to be addressed is how best to get the requisite soil amendment into the irrigation system which services the land to be treated. It is this question which the present invention addresses.
2. Overview of the Prior Art
The present invention is an improvement on the apparatus of Rivers U.S. Pat. No. 4,820,053, issued Apr. 11, 1989. While Rivers is more specific to the dissolution of gypsum as a soil amendment, the present invention is not so limited. However, Rivers was first to recognize, and then solve, the difficult problem of creating an admixture of gypsum, a substance which is recognized as extremely difficult to dissolve and to retain in a suspended state as a slurry. Rivers also recognized the difficulty of removing the resultant slurry while retaining its properties as mixed, by creating a quiescent zone from which slurry could be drawn without disturbing the delicate balance of the solution.
However, Rivers provides a system in which, by its very nature, the concentration of gypsum tends to decrease as a function of time. As a result, the user is constantly adding both the particulate gypsum and water during the irrigation cycle.
The present invention, on the other hand, provides a unique system to maintain concentration level relatively constant, which is a distinct advantage, if not an absolute necessity, in flood irrigation systems, for example.
A significant aspect of the present invention rests in the capability of the apparatus to extract, for injection into an irrigation stream, or the like, a measured amount of slurry at all times, and one aspect of the invention which assists in providing the requisite consistency is the ability of the apparatus to raise and lower the extractor during use in order to draw slurry, which is at a predetermined and constant ratio of additive to fluid. A search disclosed no device which accomplishes the foregoing in substantially the same way. Indeed, Wheaton U.S. Pat. No. 4,781,894, which is in a different field of endeavor altogether, is representative of the art currently available.